The heavy metal post box in Cecil Avenue was completely blown up, with parts of it being thrown across the pavement.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Alison Braun

It also appeared to have GR insignia embossed upon it suggesting it was pre 1952 - the GR is the “Royal Cypher” and signifies the King or Queen that was the monarch at the time when the post box was erected.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Alison Braun

A GR post box would have been put up during the era of King George VI.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Alison Braun

Alison Braun, 52, lives just up the road in MacDonald Avenue and was shocked at what had happened.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Lewis Bennett

She was grateful no-one was hurt, and was suprised at how strong the explosion from the firework had been.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Alison Braun

She said: “I honestly don’t know how it didn’t kill anyone.

Police are investigating after a post box in Cecil Avenue was blown up by a firework. Photo: Lewis Bennett

“I went to check to see if my parcel had been in it but there didn’t seem to be any post there.

“I think the postman must have been earlier in the day.”

Other residents said they heard a huge bang and went out to investigate before reporting it to the police.

It even shook the windows in some houses close to Cecil Avenue.

Brona Morgan wasn’t at home at the time, but lives opposite where the post box was.

The explosion was so powerful that it set off her CCTV camera system outside her house.

The footage shows a car drive past shortly after the explosion, and the base of the post box in flames.

Officers attended the incident and carried out door to door enquiries.